80 
GAMMARIDiE. 
as long as the head and first segment of the body ; the 
peduncle is longer than the flagellum, and the first joint 
longer than the other two, the third being shorter than 
the second. The flagellum consists of four articuli, the 
first of which supports a brush of hairs, or rather one 
or two short rows of auditory cilia — long, delicate mem- 
branous organisms, somewhat like transparent hairs, and 
evidently intimately connected with the sensation of 
hearing ; the secondary appendage is minute and slender, 
consisting of two articuli only, one much longer than 
the other. The first pair of legs are short, and have 
the coxa but little developed ; the hand is tapering, and 
furnished with two hairs near the base of the finger ; 
the finger is slightly curved, terminating in a short nail, 
and armed along the inferior margin with two minute 
spinules. The second pair of legs are long and slender, 
having the coxa deeper than that of the preceding pair ; 
the wrist is nearly as long again as the hand, and has the 
inferior margin thickly ciliated with long hairs ; the hand 
is not broader than the wrist, and has the upper and 
low r er margins nearly parallel, and thickly furnished with 
long hairs ; the inferior angle is considerably produced, 
so as to give to the organ a chelate character, although, 
from its minute dimensions, one of feeble importance. 
The finger is straight and tapering, having the apex 
subapically furnished externally with a curved spine. 
The third and fourth pairs of legs are subequal, toler- 
ably robust, and alike, except in the form of their coxae, 
which is much larger in the fourth than in the third pair, 
and has a slight emargination, corresponding with the 
margin of the anterior lobe of the coxa of the fifth pair 
of legs. The three posterior pairs of legs are also of the 
same length and form, tolerably strong, though not so 
robust as the two preceding ; their second joints are 
